Contact member



comer MEMBER.

APPLICATION FILED JAN- 5, 1917.

1,323,242; Patented Dec. 2, 1919.

j? f 8 l WITNESSES INVENTOR neously and the con act member will not be JOSEPH D. BIRRELL, 0F WI LKINSBURG, PENNSYLVANIA, ASSIGNOR TC WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORFORATION OF PENNSYLVANIA.

CONTACT MEMBER.

Specification of Letters Patent. Patented Dc, 2, 19199,

Application filed January 6, 1917. Serial No. 140,946.

To all whom it may concern Be it known that I, JosErH D. BIRRELL, a subject of the King of England, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Contact Members, of which the following is a specification.

My invention relates to contact members and particularly to contact members for circuit interrupters of the fluid-break type.

The object of my invention is to provide a contact member of the above indicated character that shall have its contact surface of such shape as to correspond to the meniscus of the fluid to thereby cause the fluid to be disengaged from all points of the contact surface simultaneously.

Heretofore, circuit interrupters have been constructed in which a contact member is adapted to break the circuit by being moved out of engagement with a conducting fluid.

-Since the fluid normally assumes a spheri the fluid will not be, disengaged from all points of the contact surface simultaneously.

In view of the above, I provide amovable contact member and so form its engaging or contact surface that it corresponds to the meniscus of the conducting fluid. Thus, when the contact member is moved out of engagement with the fluid, all points of its engaging surface a e interrupted simultapitted or burned.

In the accompanying drawings, Figure 1 is a view, partially in section and partially in elevation, of a circuit interrupter embodying my invention, and Fig. 2 is a top plan View of the contact member shown in Fig. 1.

'The circuit interrupter 1' comprises, in general, a receptacle 2, a stationary contact member 3, a movable contact member 4 and a conducting fluid 5.

The movable contact member 4 is operatively connected to an actuating rod 6 and is so cut away at its lower or contact surface mation of air pockets within the cut-away portion of the contact member 4 when the same is moved downwardly into the fluid 5. The ball 9 is adapted to be so seated when the contact member 4 is moved upwardly as to :preclude the passage of air through the valve 8. The engaging surface 7 of the contact member 1- is adapted to have a shape substantially in accordance with the meniscus of the fluid 5 in order that, when it is moved upwardly, the fluid 5 will .be disen-' gaged from all points of the contact surface simultaneously to thus preclude the contact member 4 from being pitted or burned.

If it is desired to open the interrupter 1,

the movable contact member-.4 is moved upwardly until it assumes such position that the-force of gravity and the surfacetension are such as to permit the fluid to be disengaged from the surface 7 When this condition obtains,.the fluid 5 will be disengaged from all points of the surface 7 simulta'- neously. If it is desired to again close the interrupter, the movable contact member 4 is -moved into engagement'with the fluid 5, and the air within the concave portion, at its under side, will be permitted to escape through the valve 8 to thus preclude the formation of air pockets and to permit the'interrupter to function properly when it is again opened.

In the particular application of my invenv tion illustrated, the fluid 5 is mercury and the movable contact member 4 is constructed of aluminum or] other non-amalgamating material. However, for different fluids, the shape of the contact member must conform to meniscus of the particular fluid.

While I have describedmy invention as particularly adaptable for circuit inter-.

rupters, it will be understood that. it may be used for relays and other similar devices without departing from the spirit and scope 'l of the invention, as set forth in the appended claims. I

I claim as my invention: 1. A contact member for a conducting fluid comprising a conducting member having its engaging surface so shaped as to'conffiorri to the meniscus of the conducting 2. A contact member for a fluid-break circuit interrupter comprising a conducting member having a contact surface correspending inshape to the meniscus of the fluid in which it is immersed.

3. In a circuit interrupter, the combination with a. conducting-fluidcontaining re? ceptacle, of a movable contact member having its lower contact surface so shaped as to correspond to the meniscus of the conducting fluid. A 4. In a circuit interrupter, the combination with a fluid-containing receptacle, of a contact member having a contact surface corresponding in shape to the meniscus of the fluid in which it is immersed.

5. In a circuit interrupter, the combination with a fluid-containing receptacle, of a movable contact member the contact surface of which is adapted to so conform to the meniscus of the fluid that the fluid will be disengaged from all points thereof simultaneously.

6. A contact member for a circuit interrupter of the fluid-break type having its engaging'surface so conforming to the meniscus of the fluid that the fluid will be disengaged from all points thereof simultaneously.

7. A contact member for a circuit interrupter of the fluid-break type having its engaging surface of such shape as to correspond to the meniscus of the fluid.

8. In a circuit interrupter, the combination with a fluid-containing receptacle, of a movable contact member having a concave contact surface, andmeans for precluding the formation of air pockets on the contact surface of the contact member when it enters the fluid.

In testimony whereof, I have hereunto subscribed my name this 27th day of Dec,

JOSEPH D. BTRRELL. 

